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Effect of solute concentration in osmosis
Factors affecting the osmosis
Osmosis experiment evaluation
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Recommended: Effect of solute concentration in osmosis
Investigate the factors affecting the rate of Osmosis
Planning
Osmosis is the diffusion of water from a lower concentration of solute to a higher concentration of solute, through a partially permeable membrane. In a high concentration of water the amount of solute (e.g. sucrose) is low. This could be called a weak or dilute solution. In a low concentration of water the amount of solute is high. This could be called a strong or concentrated solution. When a partially permeable membrane divides two such solutions, the water will move from the area of high concentration to the area of low concentration until both sides are equal. In plant cells water flows through the cell wall and cell surface membrane into the vacuole from the outside. As a result, the cell swells up. It doesn't burst as the cell wall stops the cell expanding too much; at this point we say a cell is fully turgid.
Aim
The purpose of my investigation is to investigate the factors affecting the rate of Osmosis. The key factors I have found affect this are:
Length - of membrane
Temperature - of water
Concentration - of solution
The factor I am going to investigate is the concentration of the solution in which the potatoes are placed. By doing this I will have to control all other factors to ensure a fair test, these are; doing all the tests at room temperature to control the temperature as a higher temperature would mean diffusion would occur quicker. The mass and surface area of the potatoes at the beginning of the experiment are other controls I will need to monitor to ensure a fair test. The mass of the potato is a dependent variable; this means that it will be measured throughout the experiment. I will measure the mass in grams correct to 2d.p. The potato chip will be measured before it is put in the solution, and after. This will allow us to see whether osmosis has taken place, and to what extent.
The volume of the solution that the potato chips are kept in must be fair. The must be totally covered in the solution, and the amount of solution will be kept the same because all the potato chips are the same size. The amount of solution I cover each chip in will be 20cm.
Prediction
I predict in my experiment that the higher the concentration of sugar in the solution, the smaller the potato chip will become. I predict this as the greater the concentration of water in the external solution, the greater the amount of water that enters the cell by
One of the last types of ways investigators are coached to detect deception is in the behavioral attitudes of a person being interviewed such as being unconcerned or over anxious (Kassin, 2005). The success rate of looking for these cues are very successful in telling if an individual is being deceitful and has surpassed any laboratory tests conducted on the subject. The laboratory test however did reveal some interesting facts. The research showed that people who had training and experience did not score better than the control group who received no training. In fact all individuals scored at the chance level with the people who had training scored just above chance or at the chance level. To check if special training in the detection of deception was more accurate a study ...
In the diagram below on the right, we see two solutions divided by a partially/selectively permeable membrane (i.e. one that is porous, but allows water molecules through faster than dissolved substances). Text Box: Originally, the two solutions were; pure water, on the left, and sugar solution with a high sugar concentration, on the right. The pure water solution is said to have higher water potential than the concentrated sugar solution, because the water will flow from the area of high concentration of free water molecules (the dilute solution), to the area of low concentration of free water molecules (the concentrated solution). In other words, to the sugar solution.
The polygraph is a very controversial topic when comes to the introduction of the techniques into court. The polygraph technique has not changed since first developed in 1895. What the polygraph does is measures the blood pressure fluctuation, pulse rate and respiratory rate changes. The rate of the blood pressure, pulse and respiratory rate not only changes due to the body being stressed because the person is lying, but it also changes due to anxiety, anger and medical conditions. This will affect the accuracy on the technique and give inconsistent readings within the results (Gailus, C., 2008, November
If a plant cell is places in a hypotonic solution the cell has a lower water concentration to that of the solution. Water will move into the cell by osmosis from a high water concentration outside the cell to a lower water concentration inside the cell through a selectively permeable membrane. The cell becomes turbid
Heart rate, blood pressure, and skin conductivity are monitored during the lie detector test, those responses can be controlled. Steve Elias writes, “Some people are so divorced from morality or a guilty conscience that they may test honest – because they are really good
A lie is a false statement with the purposely intentions to deceive, a falsehood or falsification. Since the beginning of time when Adam and Eve were created by god, and Adams fibbed about eating the apple, lying and deception has been the consistent future of human behavior or sin. The history of the polygraph has a similar long history with the reliable means of detecting deception. Researchers believed that this type of work must be viewed with care and cautiously being that the ones who tell the lies know that they are undergoing research and likewise know they do not comparatively behave as they would in real-life settings. There has been numerous of studies that attempt to identify specific verbal and nonverbal behaviors associated with lying. The polygraph does not detect a lie; it detects respiration and cardiovascular activity. The assumption is that liars will become more nervous that one who tells the truth. In the attempt to deceit the test through unconscious actions, many different behaviors have been associated with liars deception, including gazing aversion, the increase or decrease in movement, the amount of pauses or hesitations, slow of the speech rate, and speech errors.
-The cells in the body will increase because osmosis causes molecules to move from a less concentrated solution to a more concentrated solution.
Lying has been a problem since societies were first formed. Some people are great liars, others are not. But, whether someone is a good liar or not, one-tenth of a second is all it takes for subtle changes known as micro expressions to appear and disappear from a person’s face. These micro expressions are a sign of emotion. The people who read these micro expressions are human lie detectors. Although. police have machines such as the polygraph test, which measures body temperature and voice tone to help them detect when people are lying, micro expressions are far more reliable. Micro expressions are more useful to police than polygraph tests because, polygraph tests only detect spikes in emotion, there is little scientific evidence about accuracy, and micro expressions are proven to help people further scientific research.
A polygraph test can record a person's breathing rate, pulse, blood pressure, perspiration and other significant physiological changes that suggest a person is lying, but it should not be used as evidence in a court of law because it does not provide reliable proof of a person's physical reaction to the stress of lying.
Osmosis in Potato Tubes Osmosis: Osmosis is the movement of water molecules through a semi-permeable membrane from a high concentration to a low concentration. Diagram: [IMAGE] [IMAGE] Aim: To see the effects of different concentration of sugar solution on Osmosis in potato tubes. Key factor: In the investigation we change the sugar solution from: 0%-10%-20%-30%-40%-50% this is the independent variable; the dependant variable is the change in mass. Prediction: I predict that all the potato tubes in pure water or low concentration sugar solution will swell because water enters their cells by osmosis.
A polygraph is an instrument that simultaneously records changes in physiological processes such as heartbeat, blood pressure, respiration and electrical resistance (galvanic skin response or GSR). The polygraph is used as a lie detector by police departments, the FBI, the CIA, federal and state governments, and numerous private agencies. The underlying theory of the polygraph is that when people lie they also get measurably nervous about lying. The heartbeat increases, blood pressure goes up, breathing rhythms change, perspiration increases, etc. A baseline for these physiological characteristics is established by asking the subject questions whose answers the investigator knows. Deviation from the baseline for truthfulness is taken as sign of lying.
The polygraph test is conducted by using a polygraph machine. Polygraph exams can exhibit false results, in those scenarios, how can one determine these exams to be accurate? We assume that when we use polygraph tests we will
One of the components of Reid approach is training the interrogators to establish whether a suspect is lying or telling the truth by evaluating the nonverbal and verbal behavior during the interview. Many people question the effectiveness of interrogation training in assisting to discern truth from suspects. According Professor Richard Leo, people are poor in drawing accurate judgments of deception and truth (Leo, 2013). The behavior prompts used police are not diagnostic of deception, the investigators cannot differentiate false from truth denials of guilt, and yet they maintain they draw accurate
Osmosis is the passage of water molecules from a weaker solution to a stronger solution through a partially permeable membrane. A partially permeable membrane only allows small molecules to pass through, so the larger molecules remain in the solution they originated in. Solute molecule [IMAGE] [IMAGE] Water molecule [IMAGE] The water molecules move into the more concentrated solution. When water enters a plant cell it swells up. The water pushes against the cell wall and the cell eventually contains all that it can hold.
Lie detector tests, also known as polygraph tests, are barely ever used in criminal cases. The theory behind a lie detector test is that it is too stressful to lie, and that the test will be able to pick up stress associated, and read it. The term "polygraph" in Greek means "many writings". "Lie detectors are called polygraphs because the test consists of simultaneously monitoring several of the suspect's physiological functions -- breathing, pulse, and galvanic skin response -- and printing out the results on graph paper." (Lie Detector and Polygraph Tests: Are They Reliable?). When the results are printed out, the lie detector administrator can easily determine just when these biological responses occurred. If you show a maximum biologic reaction that lines up with the questions on the graph paper, this shows stress is presumed, and that stress indicates a lie. Sometime...